[clang] [clang] Cleanup IncludeLocMap (PR #106241)

[Ilya Biryukov via cfe-commits]

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@@ -453,6 +454,61 @@ TEST_F(SourceManagerTest, loadedSLocEntryIsInTheSameTranslationUnit) {
 
 #if defined(LLVM_ON_UNIX)
 
+TEST_F(SourceManagerTest, ResetsIncludeLocMap) {
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ilya-biryukov wrote:

Suggestion: add a comment explaining what this aims to test at a more detailed level. Something like:
```cpp
// Check we clear include loc caches when resetting the source manager.
```

https://github.com/llvm/llvm-project/pull/106241